1. Field of the Invention
The subject disclosure relates to compressors, and more particularly to an improved method for providing electrical connections to components within the shell or housing of a compressor.
2. Background of the Related Art
Referring to FIG. 1, a top, partial cross-sectional view of a prior art compressor 100 is shown. The compressor 100 has a shell 110 that provides a hermetically sealed environment. Use of electrical components inside the shell 110 has been widely used and well understood in the art. Great care must be taken to insure that the integrity of the hermetically sealed environment is not breached by the electrical connections.
A power terminal 112 facilitates electrical connection into the hermetically sealed environment of the shell 110. The power terminal 112 must maintain the seal while withstanding the harsh operating conditions. The power terminal 112 is disposed within an aperture in the shell 110. The power terminal 112 has a cup-shaped metal collar 126 with a bottom wall. The wall defines holes that conductor pins 128 pass through. The collar 126 is sealed in the shell aperture by welding and the pins 128 are sealed within the collar 126 by fused glass insulation. To further stabilize the terminal 112, the fused glass insulation surrounding the pins 128 is commonly covered with epoxy or shielded by ceramic collars.
A fence 130 surrounds and protects the power terminal 112. A molded plug (not shown) is configured to couple with the fence 130 and, thereby, make an electrical connection with the pins 128 outside the shell 110. To accomplish this connection, the pins 128 are often provided with a tab (not shown). A similar plug, tabs or wires must be provided on the inner end of the pins 128 to accomplish electrical connection between the compressor component and the power terminal 112.
There are problems associated with sealed glass pin power terminals 112. The terminals 112 require extensive tooling that is costly and not easily modified to add or subtract pins 128. This prefabrication process is costly, complex and time consuming. As the terminals 112 are being welded to the shells 110, the glass seals are often damaged and, thus, the assembly 120 must be scraped and replaced. This is quite costly as significant time and expense has already been invested in pre-assembling the power terminal 112. Even worse, damaged glass seals go undetected, creating eventual compressor failure. Further, it is common for the plug and, in turn, electrical connections to become loose resulting in compressor failure. These additional parts and complexity to connect to the pins 128 adds cost and creates additional junctions that may fail. For other examples, see U.S. Pat. Nos. 6,971,860; 6,372,993; 5,584,716; 5,762,479; 5,538,404; 5,281,105; 4,729,723; 4,412,791; 4,406,590; 4,396,360; 4,384,635; and 4,239,461.
There is a need, therefore, for an improved assembly and method of making the assembly which permits easy internal and external electrical connections with the hermetically sealed environment within a compressor shell and aids in assuring reliable performance while being cost effective.